ATI Libert/Freedom Custom valve

[Madd Hatter]

Look up 5 angle valve job. Heck, Billy could tell you about it I'm sure he's done a few on the Harleys he's worked on

[darkcharisma]

Look up 5 angle valve job. Heck, Billy could tell you about it I'm sure he's done a few on the Harleys he's worked on

i just looked it up, this valve actually has a 3 degree cut. yup Billy did send me a pictogram on that one

[oldpro]

I went ballistics on the angles and smoothing out for better flow. looks like i can test this new puppy as soon as my replacement oilless compressor comes in a few days for the shoebox.

note. it looks like a funnel even the valve face has an angle.

WOW good work! That should work great

[darkcharisma]

Thanks Travis, any and all inputs are always encouraged

[darkcharisma]

thank you Billy i hit 1023fps shooting 26.1 grains with your plenum. while doing 951fps without. and thank you Stephen for sending the slugs.

last night i tested the Liberty and the custom valve, lets call it the DC valve. i love every thing about the Liberty except the small plenum and the spiky regulator.

when i said spiky, i mean it spikes from 16mpa to 19mpa, from 24mpa it spiked to 28mpa. no kidding, i want to get rid of it and run it unregulated unless someone can find out how to fix the regulator spike.

okay here is the testing data from oem barrel port to ported with Gary's DC valve. thanks for your patience Gary. sorry no Oem valve tested.

first test:
  NO PLENUM, no barrel port.
  14.3gr=883fps@19mpa with 80grains hammer weight. 840fps without hammer weight.

Oem plenum, no barrel port.
 14.3grs=1071fps@19mpa with hammer weight. 28.6grs=797fps

test #2 and after uses hammer weight and oem plenum unless noted.
 3/16 barrel port. 14.3gr= 1141fps@19mpa. 28.6gr=785fps@19mpa. 28.6gr=765fps@14mpa

test #3
 .217 barrel port. 14.3=1128fps@19mpa. 28.6gr=800fps@14mpa

26.1gr avs slugs @19mpa=878fps
26.1gr avs slugs @14mpa=809fps
===========================
test #4: shooting 28.6 and 26.1 grains in between.
4ksi fill, 24mpa reg, 28.6grs, oem plenum, shot string.

866,866, 913, (26.1gr)951, 918, (26.1gr)944, 896,900, 894, 884, 881, (26.1gr)896
===========================
final test:
  24mpa,28.6gr, 3.8k fill. BILLY'S PLENUM (15.2cc) with in breech plenum=18.2cc

877,863, 873, 957(3600psi), (26gr) 1023fps. (26grains) 1013fps. ending pressure is 3400psi.

If the regulator did not spike from 24mpa to 28mpa at a bit over 4ksi fill, then the Liberty could have given us 10 usable shots at 24mpa reg set point. it is using only 50psi per shot as i looked at the gauge after each shot.

this concludes the testing for the Trench valve without modifying more components. i can still push it faster if i mod something here and there.

more testing coming soon with the one hole exhaust.

This valve and the poppet design did not want to seal on slow filling compressors like the shoebox so i had to use a stronger spring. so no data gained from the lesser strong spring...it could be a minuscule gain.

next time i will mate a digital gauge to the exhaust side and find out if the 24mpa is retained through the shot.  i soooo am looking forward to that!!!!

[rsterne]

That data lost me completely.... At what point in the testing did you change from the stock oem valve to the DC valve?....

Bob

[darkcharisma]

its rough data but the best i could do last night. i did not use oem valve at all. just documenting the mods from oem barrel to .217 barrel port. using the ported .217 TP in the breech.

[cosmic]

WOW Duy, the new valve looks GREAT !!!!!

[darkcharisma]

WOW Duy, the new valve looks GREAT !!!!!

Ray your reg is not set as high as this one i tested...what does that mean?   

i gonna dig into your rifle and dwell there for a bit. and when i am done its going to roar!

or goes kaboom pow. lol

[cosmic]

Thanks Duy , hope it not kaboom pow !!

[Madd Hatter]

This valve and the poppet design did not want to seal on slow filling compressors like the shoebox so i had to use a stronger spring. so no data gained from the lesser strong spring...it could be a minuscule gain.

That is something I also thought that the poppet spring needed to be stronger and then maybe the rifle wouldn't dump all of it's air below 2000 psi?

[Madd Hatter]

WOW Duy, the new valve looks GREAT !!!!!

Ray your reg is not set as high as this one i tested...what does that mean?   

i gonna dig into your rifle and dwell there for a bit. and when i am done its going to roar!

or goes kaboom pow. lol

About where was the wheel set from stock? I realize that that won't directly correlate form one rifle to the next but it's a start for those of us without a plenum gage.

[cosmic]

Brother Duy, this is a work of art, Beautiful !!!  The one hole without the trench might get it to POP !!
    Bob F, the regulator adjuster was in the stock position when tested.. 
    Reg pressure about 2600 -2900 psi !!

[Madd Hatter]

Brother Duy, this is a work of art, Beautiful !!!  The one hole without the trench might get it to POP !!
    Bob F, the regulator adjuster was in the stock position when tested.. 
    Reg pressure about 2600 -2900 psi !!

I thought the stock position of the reg was suppose to be 13 and 14 mpa? That's what the assembly instructions say. I feel that the single hole will work better but what do I know. lol

[darkcharisma]

hey Robert, yes it should be 14mpa, with my liberty anyway.

i dont remember the positions now. i just measure the depth of the brass wheel now. mines 0.025 deep from flush. i think its more consistent that way too. just dont go more than 3600psi. thats the max for the receiver i think, you can see it indicated on the freedom too.

on the dumping air after 2000psi. stronger spring may help, but i would just pull the lever back. or dont shoot down to 2000psi. i ran out of stronger conical springs, only had a couple.

[cosmic]

Not sure since my rifle has been adjusted so many times ......

[Madd Hatter]

hey Robert, yes it should be 14mpa, with my liberty anyway.

i dont remember the positions now. i just measure the depth of the brass wheel now. mines 0.025 deep from flush. i think its more consistent that way too. just dont go more than 3600psi. thats the max for the receiver i think, you can see it indicated on the freedom too.

on the dumping air after 2000psi. stronger spring may help, but i would just pull the lever back. or dont shoot down to 2000psi. i ran out of stronger conical springs, only had a couple.

So at .025 depth what did the mpa end up being?

[darkcharisma]

Robert thats 3600psi at that depth. i wonder if Mark will offer the extensions with gauge for sale? Mark you should.

i have some dies coming in to do something similar for ease of operation. currently i have to take the adapter on and off each time to set it. a pain. the thread is m10x1.25 so theres not any mpa gauge with that thread.

[Madd Hatter]

Yeah, I noticed that all of the gages are 10x1 mm. Bummer,

[USAFANG6799]

Duy -

an out of stronger conical springs, only had a couple.

Do you have a part number and the source for the stronger conical spring?
Like to try it to see if it takes care of the air dump.

Keep up the GREAT R&D on the Liberty/Freedom.
Very interesting gun to say the least.